Dark Energy in vector-tensor theories of gravity

Abstract

We consider a general class of vector-tensor theories of gravity and show that solutions with accelerated expansion and a future type III singularity are a common feature in these models. We also show that there are only six vector-tensor theories with the same small scales behavior as General Relativity and, in addition, only two of them can be made completely free from instabilities. Finally, two particular models as candidates for dark energy are proposed: on one hand, a cosmic vector that allows to alleviate the usual naturalness and coincidence problems and, on the other hand, the electromagnetic field is shown to give rise to an effective cosmological constant on large scales whose value can be explained in terms of inflation at the electroweak scale.

4 pages, 1 table. Contribution to the proceedings of Spanish Relativity Meeting 2009, Bilbao, Spain, 7-11 September 2009

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• Cosmology and the Fate of Dilatation Symmetry
• Gauss-Bonnet Quintessence: Background Evolution, Large Scale Structure and Cosmological Constraints
• A cosmic vector for dark energy
• Cosmological evolution in vector-tensor theories of gravity
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Cited by in corpus (2)

• Cosmological perturbation theory in Generalized Einstein-Aether models
• Loop Quantum Vector-Tensor Gravity and Its Spherically Symmetric Model